Immunization rates for hepatitis A, a virus that lives in faeces, need to be raised as soon as possible, because the rate of infection is spiking in the United States, Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, said Tuesday.
A person recently confirmed to have hepatitis A has been identified as the first case in the country among those vaccinated but not yet had an immune booster shot, Fauci said at a briefing in Bethesda, Maryland.
Hepatitis A, which can be serious, costs millions of dollars to eradicate. Vaccination is one of the few forms of vaccination that, once widely used, has not been abandoned or fully implemented.
In the past two decades, all states have adopted a policy of vaccinating people before they drink drinking water, and some people continue to question the effectiveness of the vaccine. During those years, clusters of hepatitis A have occasionally been reported in states where there were not vaccination programs.
The Health and Human Services Department said Tuesday that there are hepatitis A cases being reported in Florida, Ohio, Maryland, North Carolina, Pennsylvania, Texas and Virginia. The department has reported two deaths. Hepatitis A outbreaks have also been reported in Puerto Rico, the U.S. Virgin Islands and other parts of the Caribbean.
The outbreak that erupted in the Caribbean last year killed nearly 600 people, and it continues in the majority of countries where it is being reported. People most at risk are those who regularly visit Puerto Rico, as well as people who are treated in San Juan’s hospitals.
Symptoms include jaundice, fatigue, loss of appetite, nausea, diarrhea, vomiting, stomach pain, fever and fatigue. People can also develop jaundice within days of exposure to feces from a person infected with hepatitis A.
As of July 31, the Centers for Disease Control and Prevention had recorded 516 confirmed cases of hepatitis A in 19 states and Washington, D.C. Most of those who tested positive lived in Puerto Rico. A total of 738 people were under immunization to protect against hepatitis A, including 67 children younger than 6 months old. The outbreak has been going on for more than five months.
“We have tried to contain the outbreak,” Fauci said. “There are a number of people at risk, particularly individuals who use tobacco and alcohol — people who are working in health care.”
Because of the outbreak, the government is ordering a large vaccination campaign, the length of which has not been determined.
Unlike earlier hepatitis A outbreaks, which were confined to just one region, the current outbreak has spread into the United States and to Mexico, beyond the Caribbean.
A study presented in April at the American Association for the Study of Liver Diseases conference found that the U.S. vaccine to prevent hepatitis A was only 40 percent effective, the difference between the effectiveness of the vaccine in preventing infection and the ability of the virus to spread among humans.
In 2016, 80 people acquired hepatitis A virus from large injections of a genetically engineered form of the vaccine, and two were vaccinated to prevent an infection, said Dr. Nidal Khatib, of the University of North Carolina, Chapel Hill, who led the study.
The study identified three major problems with the vaccine used in the United States and Europe.
First, it lacked an effective way to build immunity in the first two years after vaccination.
A second concern was that the vaccine did not help fight hepatitis A in adults who have been exposed to it, people who are not exposed to hepatitis A at all.
And a third was the vaccine, which was invented in 1956, was too old to be effective in preventing the disease. In March, Fauci announced that Fauci’s NIH was working with five drug companies to develop a vaccine that would be effective.
Hepatitis A causes inflammation of the liver, which can be treated by many medications. Unlike polio, which spreads through person-to-person contact, hepatitis A spreads in an aerosol, where the virus is absorbed through the mucus membranes of the mouth.
The disease is spread by eating food or drinking water that has been contaminated with feces, which is how it is spread from one person to another. It is also spread from person to person through contact with infected wounds.
Hepatitis A is also transmitted through small cuts, but that way is much more difficult to track, because it usually is not life-threatening, or at least not immediately life-threatening.